Process for production of puffed fabrics



D. D. MCCORD ETAL 2,757,434 PROCESS FOR PRODUCTION OF PUFFED FABRICSFiled March 51, 1955 2 Sheets-Sheet l INVENTORS: 00061.45 0- McC RDTHOMAS R. HQLBROOK y CHARLES A. RUDOLPH ATTORNEY-3.

1956 n. D. M CORD ETA PROCESS FOR PRODUCTION OF PUFFED FABRICS FiledMarch 31, 1955 2 Sheets-Sheet B .INVENTO 5 DOUGLAS 0. c 0R0 THOMAS R.HaLBRooK BY CHARLES ARI/0041M! ATTORNEYS,

United States Patent PROCESS FOR PRODUCTION OF PUFFED FABRICS Douglas D.McCord, New York, N. Y. and Thomas R.

Holbrook and Charles A. Rudolph, Cornelia, Ga., assignors to ChicopeeManufacturing Corporation, Chicopee Falls, Mass., a corporation ofMassachusetts Application March 31, 1955, Serial No. 498,286

4 Claims. (Cl. 28---72) The present invention relates to a novel processfor the production of woven fabrics having puffed portions to providethree-dimensional patterns thereon. The puffed fabrics produced inaccordance with our novel process are advantageously useful asupholstery fabrics, particularly, automobile upholstery.

Objects and advantages of the invention will be set forth in parthereinafter and in part will be obvious herefrom, or may be learned bypractice with the invention, the same being realized and attained bymeans of the steps and processes shown and described herein.

The invention consists in the novel steps and processes shown anddescribed herein.

The production of puffed fabrics is not new. Various methods ofproducing these known puffed fabrics have been used employing differenttypes of filaments. In one known method, heat shrinkable filaments arewoven with non-shrinkable filaments to form a fabric body which whensubjected to a heat treatment forms the desired puffs, due to theshrinking of the heat shrinkable filaments. In another modification,fabrics made of yarns or filaments of a thermoplastic material areheated on one side only, causing the formation or buckling of the fabricwith the formation of a three-dimensional pattern effect. The patternsproduced in accordance with the prior processes are not entirelysatisfactory, however,

for the puffs produced are often not as sharp and accentuated asdesired. Moreover, the patterns formed by the puffs are not alwaysretained while the fabric is in use.

The object of the present invention is to provide a simple and efficientprocess whereby puffed fabrics having sharp and accentuated puffs may bereadily produced. A further object of our invention is to provide anovel process for producing a puffed fabric, wherein the pattern designformed by the puffs retains its original appearance after the fabric hasbeen in use for a considerable period of time.

Broadly, our process relates to a differential heat treatment processwherein a fabric, having heat shrinkable shrinkers incorporated on itsmain body, is subjected to a selective differential heat treatmentwhereby heat is transmitted primarily to the portions of said shrinkersadjacent the back of the fabric, causing said portions to shrink, whichin turn causes the main body adjacent thereto to rise, thus forming thedesired puffs. In order to carry out the foregoing selective heattreatment, wherein the heat is transmitted primarily to the portionsofthe shrinkers on the back of the fabric, rather than the main body orthe portions of the shrinkers adjacent the front face, two essentialconditions are necessary, first, the shrinkers are incorporated on themain body in such a manner that they are floated predominantly at theback of the main body, and, secondly, that during the heat treatmentstep the temperature at the back of the main body be higher than thetemperature at the face of the fabric. By the term floated, as usedhereinabove and hereinafter, is meant that the shrinkers are not in-Patented Aug. 7, 1956 terwoven with the fibers of the main body butinstead pass over or under a plurality of threads of the main body.

The shrinkers, floated predominantly to the back of the main body, maybe secured in a variety of configurations in order to produce differentpattern designs. Preferably, they are secured on the main body in themanner disclosed in co-pending application Serial No. 498,306, filedMarch 31, 1955 by Douglas D. McCord, Harold P. Paris and Bernard R.Koenig. In this application there are disclosed puffed fabrics producedby floating the shrinkers predominantly on the back side of the mainbody of the fabric in such a manner that the puffs formed on shrinkingof the shrinkers are defined where the shrinkers intersect the main bodyof the fabric. Also, as disclosed in said co-pending application, it ispreferred that the shrinker's be floated slightly over the face of themain body of the fabric to accentuate and increase the sharpness of thepuffs formed.

The differential heat treatment utilized in our process, whereby heat istransmitted primarily to the shrinker portions on the back of thefabric, may be carried out in various ways in order to provide a highertemperature at the back of the fabric than the front of the fabric. Inone modification as illustrated in the accompanying drawings, the fabricwith attached shrinkers is passed over a series of heated drums, whereinonly the back side of the fabric contacts the heated surface of thedrums to provide the required heat differential between the back andfront of the fabric. The exposed shrinker portions on the back of thefabric, on contact with the heated surfaces, are caused to shrink,producing the desired puffs on the front face of the fabric. The bodyportion of the main body of the fabric adjacent the shrinkers is causedto rise on the shrinking of the shrinkers due to the grip exerted by theshrinkers where they intersect the main body portion.

Another method of effectuating the required heat differential is bypassing hot gases, such as hot air, over the back side of the fabric andpassing cool gases, such as cold air, over the face of the fabric.

As will be evident to those skilled in the field, the required shrinkingtemperature will vary depending upon the particular thermoplasticcomposition of the shrinkers. Also, the time of heat treatment varies;with the particular thermoplastic composition used, as well as thetemperature employed. Higher temperatures require less time to producethe desired shrinking than when minimum shrinking temperatures are used.

By utilizing the present process featuring a selective heat treatment ofthe shrinkers on the back of the fabric,

the filaments forming the main body and the filaments forming theshrinkers may be of the same chemical composition. The aforesaidfilaments, whether used as shrinkers or in the main body of the fabric,may be in the form of monofilaments, twisted multifilament strands, yarnspun from filament staple, etc. Likewise, filaments, different inchemical construction but having substantially the same shrinkagecharacteristics,- may also be used for bothe the main body and theshrinkers. Preferably, however, the filaments forming the shrinkers havehigher initial shrinkage characteristics than the filaments forming themain body of the fabric, since by providing a shrinkage characteristicdifferential, deeper puffs are produced: than when the shrinkers and themain body are of the same material.

The preferred materials for forming the main body of the fabric and theshrinkers are those of the saran family of copolymers disclosed inco-jending application S'erialNo. 4983199 filed March 31, 1955, by l.Ferrell Nicholl. The applicant in this application incorporates on amain body of a fabric woven from a saran copolymer, such as Saran 11S,shrinking floats or shrinkers formed of a different saran copolymer,such as Saran. 23S, whereby the filaments forming the shrinkers havehigher initial shrinkage characteristics than the filaments forming themain body, but which have substantially the same shrinkagecharacteristics after the initial shrinking step. Thus, by usingfilaments having such shrinkage characteristics, all of the filamentswill shrink at the same rate after the formation of the puffs formed bythe initial shrinking step, so that the appearance of the pattern formedby the puffs is retained in use of the fabric.

In order to describe our invention more specifically, reference is nowmade to the drawings. Figs. 1-5 show a fabric having incorporatedshrinkers floated predominantly on the back of the main body of saidfabric, the puffs on said fabric having been produced by subjecting saidfabric to a differential heat treatment illustrated diagrammatically inFig. 6. The particular mechanical structure of the fabric of Figs. 1-5does not constitute a part of the present invention, but rather theselective heat treatment process for the production of the puffs on thefabric.

Fig. 1 is a view of the face of a puffed fabric produced by theincorporation of heat shrinkable floats or shrinkers on the main body ofthe fabric and subjecting the fabric to a heat shrinking operationwhereby the heat is transmitted primarily to the portions of theshrinkers floated on the back side of the main body of said fabric.

Fig. 2 is a view of the back of the puffed fabric of Fig. 1.

Fig. 3 is a greatly enlarged schematic view of the area enclosed by dotand dash lines, as shown in Fig. 1, but before the fabric has beensubjected to the differential heat treatment of Fig. 6.

Fig. 4 is a section along the line 44 of Fig. 3.

Fig. 5 is similar to Fig. 4, but indicating the configuration of thefabric after the differential heat shrinking operation has taken place.

Referring now to Figs. 1-5, there is illustrated a fabric which, whensubjected to the differential heat shrinking operation of Fig. 6, formsa diamond pattern seen pictorially in Fig. 1, due to the formation ofpuffs 1. The main body 3, Woven of weft thermoplastic threads 4 and Warpthermoplastic threads 5, has incorporated thereon heat shrinkableshrinkers 2. Shrinkers 2 are incorporated on main body 3, in a weft orfiller direction, by floating the shrinkers predominantly at the back 6of the main body to form shrinkers portions 211 and slightly over theface 7 of the main body to form shrinker portions 2b.

As shown in Fig. 6, the fabric 3, such as the embodimerit of Figs. 1-5,is rolled on a let off roll 8 rotatably mounted on shaft 8'. Fabric 3 isthen forwarded over a plurality of internally heated drums 9, 10 and 11,each of said drums being rotatably mounted at their ends on hollow stubshafts 12, said shafts 1.2 extending only partly into the interior ofsaid drum to permit the passage of steam thereto so that the drums areinternally heated. Fabric 3 is passed over said drums 9-11 so that theback 7 of the fabric contacts outer heated surfaces of the drums wherebythe shrinker portions floated at the back of said fabric are heated tocause a shrinking thereof, which in turn causes the formation of puffsat the front of the fabric. The puffed fabric is then passed from drum11 to take up roll 13 mounted on shaft 13', said shaft 13' being drivenby power driven pulley 14. Hence drums 9-11 are fabric driven so that asthe fabric shrinks warpwise, the successive drums 9-11 are driven atdecreasing linear speeds. In order to guide the fabric as it passes overthe drums 7 guide rolls 15-20 are provided adjacent the drums 9-11.

By heating the fabric in the foregoing manner, heat is transmittedprimarily to the portions 2a of the shrinkers floated on the back of themain body. This causes the shrinker portions 2a to shrink from theirposition shown in Fig. 4 to that of Fig. 5; which, in turn, causes thewarp threads 5a over said portions 2a to be pulled together, whereuponthe body portion of the fabric adjacent said shrinker portions risesabove the front face of the fabric to form the desired puffs. Also, byfloating the shrnkers over a number of warp threads 5b, the warp threads5a do not rise tangentially from the front face but at an angle, whichcontributes to the formation of sharp and accentuated puffs.

Our novel process provides a simple, efficient method of producingpuffed fabrics of highly attractive three-dimensional appearance. Thepuffs produced in accordance with our process are sharp and accentuated,and the pattern formed thereby is retained while the fabric is in use.The fabrics in addition to the foregoing also possess de sirablebreathing properties which make them particu larly useful in automobileupholstery. By breathing properties is meant that the fabrics aresufficiently porous to provide adequate ventilation. Thus, my fabricsmay readily be used as seat covers without causing discomfort to any onecoming in contact therewith.

The invention in its broader aspects is not limited to the specificprocesses and steps described but departures may be made therefromwithin the scope of accompanying claims without departing from theprinciples of the invention and without sacrificing its chiefadvantages.

We claim:

1. A process for the production of a puffed fabric from a fabricstructure having a main body consisting predominantly of thermoplasticfilaments and having heatshrinkable thermoplastic filaments floatedpredominantly at the back of said main body and across areas in whichthe desired puffs are to be formed, said process comprising heating saidfabric structure differentially by transmitting heat primarily to saidheat-shrinkable thermoplastic filaments floated predominantly at theback of said main body, the temperature at the back of said fabricstructure being higher than at the front thereof and being sufficientlyhigh to cause said heat-shrinkable thermoplastic filaments floatedpredominantly at the back of said main body to shrink so as to form thedesired puffs in said areas.

2. A process as defined in claim 1, wherein the diflerential heattreatment is effectuated by contacting the back of said fabric structurewith a hot gas and the front of said fabric structure with a cooler gasto provide the desired temperature differential.

3. A process as defined in claim 1, wherein the differential heattreatment is effectuated by passing the back side of the fabricstructure over at least one heated drum so as to cause the portions ofthe shrinkers floated at the back thereof to contact heated surfaces ofeach drum to cause a shrinking thereof.

4. A process as defined in claim 3, wherein the fabric structure ispassed over a plurality of internally heated, freely rotatable drums,said drums being driven by said fabric material as it passes thereover.

References Cited in the file of this patent UNITED STATES PATENTS2,332,485 Hanson Oct. I9, 1943 2,401,829 Kahil June 11, 1946 2,490,830Kahil u June 11, 1946 2,524,895 Dodge Oct. 10, 1950 2,539,301 FosterJune 23, 1951 2,607,104 Foster Aug. 19, 1952 2,632,230 Neisler Mar. 24,1953 2,635,648 Foster Apr. 21, 1953 FOREIGN PATENTS 465,661 GreatBritain May 11, 1937 145,840 Australia Mar. 24, 1952

